The present invention is directed to a hand-held device including a holder for a working tool and sensing means for initiating a switching operation. The sensing means checks the configuration of a work tool inserted into the holder and cooperates with a sensor in the device. The sensing means includes at least one control element movably displaceable within an opening in the holder with the axis of the opening extending transversely of the axis of the holder, and a sensing member cooperating with the control element.
An electrically operated hand-held device for automatically adjusting to various modes of operation is known from the U.S. patent application 134,516. In such device, there is a sensing mechanism for initiating the switching operation. The configuration of the shank of the working tool inserted into the holder is sensed and evaluated for effecting the switching operation. The sensing mechanism includes a slide, adjusted in the axial direction of the holder, and one or more control elements at which the slide is axially supported in accordance with the configuration of the working tool.